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            <h2 class="title" style="clear: both"><a id="secondaryCursor"></a>
        
        <span>Using Cursors with Secondary Databases</span>
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      <p>
        Just like cursors on a primary database, you can use 
             
            <span>cursors on secondary databases</span> 
        to iterate over the records in a secondary database. Like

          
         <span>cursors used with primary databases,</span> 
        
        you can also use 
          
         <span>cursors with secondary databases</span> 
        to search for specific records in a database, to seek to the first 
        or last record in the database, to get the next duplicate record, 
            
        and so forth. For a complete description on cursors and their capabilities, see
        <a class="xref" href="Cursors.html" title="Chapter 4. Using Cursors">Using Cursors</a>.
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      <p>
        However, when you use 
             
            <span>cursors with secondary databases:</span> 
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            Any data returned is the data contained on the primary database
            record referenced by the secondary record.
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            You cannot use <code class="literal">DB_GET_BOTH</code> and related flags with
                <code class="methodname">DB-&gt;get()</code>
                
            and a secondary database. Instead, you must use 
                <span><code class="methodname">DB-&gt;pget()</code>.</span>
                
            Also, in that case the primary and secondary key given on the call to 
                <code class="methodname">DB-&gt;pget()</code>
                
            must match the secondary key and associated primary record key in
            order for that primary record to be returned as a result of the
            call.
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        For example, suppose you are using the databases, classes, and key
        
        <span>extractors</span>
        described in <a class="xref" href="keyCreator.html" title="Implementing Key Extractors">Implementing Key 
        
        <span>Extractors</span>
        </a>. 
        Then the following searches for a person's
        name in the secondary database, and deletes all secondary and primary
        records that use that name.
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      <pre class="programlisting">#include &lt;db.h&gt;
#include &lt;string.h&gt;

...

DB *sdbp;          /* Secondary DB handle */
DBC *cursorp;      /* Cursor */
DBT key, data;     /* DBTs used for the delete */
char *search_name = "John Doe"; /* Name to delete */

/* Primary and secondary database opens omitted for brevity. */

/* Get a cursor on the secondary database */
sdbp-&gt;cursor(sdbp, NULL, &amp;cursorp, 0);

/*
 * Zero out the DBT before using it.
 */
memset(&amp;key, 0, sizeof(DBT));
memset(&amp;data, 0, sizeof(DBT));

key.data = search_name;
key.size = strlen(search_name) + 1;

 
/* Position the cursor */
while (cursorp-&gt;get(cursorp, &amp;key, &amp;data, DB_SET) == 0)
    cursorp-&gt;del(cursorp, 0); </pre>
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